A traditional passive tap recording technique includes recorders that are deployed along routes of communications. In this technique, each recorder operates similar to a “sniffer” by analyzing pass-by communication packets. The recorder records the packets corresponding to certain communication sessions based on its configuration. FIG. 1 shows a typical deployment of passive tap recorders in a contact center. In an IP telephony environment, recorders are typically deployed either at the voice gateway, which interfaces between Internet Protocol (IP) network and public switched telephone network (PSTN), or at switches in order to stay along the routes of the communications. This technique has the advantages of (1) minimum intrusion to a communication system, (2) cost effectiveness in deployment for companies with centralized office locations, and (3) easy scalability for compliance recording. However, for companies with many distributed branch offices, the above advantages start to diminish. This is especially true if the purpose of the recorders is for quality monitoring.
With the growing usage of Voice over Internet Protocol (VoIP) technology, many telephony-based businesses, such as customer centers, are adopting distributed telephony systems with local access to PSTN, which are still controlled by centralized soft switches. Many customer centers are using at-home agents with soft-phones on their personal computers (PCs). Hence, some of the communications in the distributed telephony system may not be “along the communication route” that is needed for passive tap recording. Secondly, network security has now become a concern. The deployment of encryption technology has made passive tap recording become even more problematic.
In addition, many customer centers deploy recorders for quality monitoring purposes, instead of compliance. In this regard, only a small percentage of the communications are recorded, monitored, and sampled. However, to assure the accuracy of the sampling, communications are randomly selected for recording across all branch offices. With passive tap recording, a large number of recorders are potentially required and each recorder may have low usage.
A typical IP-based customer center using the passive tapping “sniffing” recording method is shown in FIG. 1. Two branch offices are shown in the figure. To communicate with any agents at the customer center, a customer communication device, such as a time domain multiplexing (TDM) or an IP phone, first sends communication signals to a call-processing device of the customer center, such as a soft switch. The communication signals can be sent either directly to the call-processing device in case of IP to IP communications or via a media processing device, such as a voice gateway in case of TDM to IP. The communication network can be a PSTN network or IP-based network. Once the communication signals have been received, the call-processing device then routes the communication signals to an agent phone.
After several rounds of communication signals exchange, media communications between the agent's phone and customer's phone can proceed via media processing device and distribution devices. The distribution devices are network routers and switches. In order to record the media communications using passive tapping, recorders are deployed at the media processing device or distribution devices using the network traffic monitoring or duplicating features, such as the Cisco's Switch Port Analyzer (SPAN) feature, on these devices. These tapping features are often available to the recorders that are directly connected to the media processing device or distribution devices, namely to recorders deployed at each branch office. Hence, a large customer center having multiple branches, such as a branch in New York, a branch in Los Angeles, and a branch in Chicago, may need multiple recorders in each branch to record the voice communications.